Current-collecting device.



L. C. NICHOLS.

CURRENT COLLECTING DEVICE. APPLICATION FILED MAYI5, 1914.

1,243,204. Patented Oct. 16,1917.

UNITED STATES PATENT OFFICE.

LOUIS C. NICHOLS, NORWOOD, OHIO, ASSIGNOR, TO ALLIS-CI-IALMERS MANUFAC- TURING COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF DELAWARE.

CURRENT-COLLECTING DEVICE.

Specification of Letters Patent.

Application filed May 15, 1914. Serial No. 838,885.

T 0 all whom it may concern Be it known that LOUIS G. NICHOLS, a citizen of the United States, residing at Norwood, in the county of Hamilton and State of Ohio, has invented a certain new and use ful Improvement in Current-Collecting Devices, of which the following is a specification.

This invention relates in general to dynamo-electric machines, and has particular relation to devices for collecting current from or passing current to the armature windings of machines of the commutator type.

In assembling such dynamo-electric machines-of the commutator type as are provided with a plurality of brushes and holders and cross-connectors between brushes of the same polarity, it is highly desirable that these devices be capable of being assembled independently of the casing or other part of the machine, and in such form that the combined brushes, brush-holders and cross-connectors can be mechanically and electrically connected to the machine proper by a comparatively simple operation.

An object of this invention is to provide a brush-holder and cross-connecting device of improved construction, and capable of being assembled as a unitary device and independently of the casing or other part of the dynamoelectric machine.

A further object of this invention is to provide a brush-holder of improved construction, which is comparatively simple in design and eiiicient in operation.

These and other objects are attained by this invention, the various novel features of which will appear from the description and drawings, disclosing one embodiment of such invention, and will be particularly pointed out in the claims.

In the accompanying drawings:

Figure 1 represents a section through the commutator end portion of a dynamo-electric machine, a portion of the casing being broken away, showing, in elevation, a current-collecting device embodying features of this invention.

Fig. 2 is a view in elevation of the current-collecting device shown in Fig. 1, before being placed in position on the machine, the view being taken from the outside of the device, or the side which is remote from the core of the machine when the device is in operative position.

Fig. 3 is an enl. rged bottom view of a portion of the device shown in Fig. 2, and shows the manner of mounting the device in operative position on a machine.

Fig. 4 is a section on the line 4--4 of Fig. 3.

Fig. 5 is a view in elevation, with parts in section, of a detail, showing the manner of securing a spring follower in position.

As shown in the drawings, the 'OI'OSS-CO11 nectors 11, 12 are of approximately the same size, being semi-circular in shape, and, preferably, stamped from sheet copper or brass, each being provided with three through openings, two of said openings being adjacent the ends and the other one at the middle. These cross-connecting pieces are mounted on spaced rods, 13, 14, 15, 16, preferably threaded throughout their length, the rods 13 and 15 being electrically connected to the cross-connector 11, and the rods 14 and 16 being electrically connected to the cross-connector 12. The rod 14 is insulated from the connector 11, and the rod 15 is insulated from the connector 12.

The preferred manner of securing the cross-connectors in place on the rods is through the use of nuts, such as 17, 18, 19, 20, on rods 13 14, 15, 16, respectively. The connector 11 is set on the rods 18, 14 and 15, and in electrical contact with the rods 13 and 15. The nut 18 on the rod 14 is spaced from the connector 11 by an insulating washer 21, and the rod 14 is spaced from the connector 11 by a suitable insulating bushing, similar to that shown at 24 in Fig. 3. The connector 12 is set on the rods 14, 15 and 16, being electrically connected to the rods 14 and 16 and insulated from the rod 15, as by a washer 25. The connector 12 is spaced from the connector 11, as by means of washers, similar to 25, on the rods 14 and 15. The connectors are held in place on the rods against the abutment nuts 17, 18, 19, 20, by nuts, similar to 26, on the front side of the connectors, the nuts 26 on the rods 14 and 16 being electrically connected to the connector 12, and the nut 26 on the rod 18 being electrically connected to the connector 11. The nut 26 on the rod 15 is spaced from the connector 12 by an insulating washer 25.

It will be obvious that the rods and crossconnectors form supporting means for one another, and that alternate rods are in electrical contact with the same connector. The preferred manner of connecting the rods to the cross-connectors is to solder the nuts that electrically engage the respective cross-connectors, to both the respective rods and crossconnectors.

On the forward end of each of the brush rods, and held between the spaced nuts 31 and 32, is mounted a brush-holder 33. This brush-holder is preferably formed from a single piece of sheet metal, as by being stamped therefrom, and comprises a plurality of parallel arms 34 and 35, having, at one end, alined openings through which a brush rod is adapted to pass, and, at the other end, being so bent as to form a recessed portion 36 for the reception of a brush 37.

A member 38 is held in position, between the apertured ends of the arms 34 and 35, by the nut 32, when. the same is screwed to holding position. This member 38 is, preferably, in the form of a bent strip of sheet metal, being enlarged at one end portion, as indicated at 39, which portion is adapted to extend beyond the periphery of the apertured end portions of the arms 34 and 35, when the parts are assembled. This enlarged end is preferably of greater width than the remainder of the member. At the other end, the member 38 is bent at approximately right angles to form an extension 41 and is apertured beneath such extension to receive a screw 42.

The screw 42 is threaded into the end of a helical spring 43 and serves to hold this end of the spring in close engagement with the abutment port-ion of the member 38. The preferred manner of securing the screw within the spring is to grind off the end of the spring approximately square, the end of the wire forming the spring being then tapered and capable of riding along the thread of the screw to a certain point, this form of threaded engagement serving to lock the screw in position against accidental movement due to vibration of the parts. An insulating washer 45, of comparatively hard material, is secured to the other end of the helical spring 43 by means of a screw 46 passed therethrough and threaded into this end of the spring, in a manner similar to that described in connection with screw 42 at the other end of the spring. In the operation of the device, this member 45 is intended to bear on the end of the brush 37 in the brush-receiving recess 36, to urge the brush against the commutator, indicated at 40.

In the normal condition of the spring, its axis is a straight line perpendicular to the abutment portion of the member 38.

As shown in Fig. 4, this spring is capable of being flexed, and, when in flexed condition, tends to return to normal position, the returning force varying approximately as the degree of flexure. It will be obvious, then, that the pressure of the spring arm on the brush may be made anything desirable by adjusting the normal position of the spring, which can be accomplished by loosening the nut 32 and shifting the member 38 to any desired extent, through the extending finger piece 39. The abutment member 38 is held in adjusted position by the frictional engagement between said member and the arms 34 and 35, due to the nut 32.

The brush 36 is electrically connected to the brush rod by means of a pig-tail connection 47, embedded at one end, in the brush, and secured, at the other end, to a washer 48, which is held in place and electrically connected to the brush red by nuts 31 and 49 on the rod.

It will be obvious that the brush-holders and spring followers may be assembled in place on the brush rods and the brushes may be loosely held in place on the rods 13, 14, 15, 16, by means of the pig-tail connections. Hence, it is possible to completely assemble the bruslrholders, brushes and cross-connectors independently of the casing or other portion of the machine.

The brushes, brush-holders and cross-connectors may be secured in operative position on a dynamo-electric machine by passing the ends of the brush rods that extend beyond the cross-connectors, through suitable openings, such as 51, in an end portion of the casing 52 of the machine, as shown in Fig. 3. The rods may be insulated from 1 5 the casing by insulating bushings 53, and are held in place on the casing by nuts 54 on the outer side thereof. The nuts 54 are insulated from the casing by means of washers 55, and the nuts 19 on the brush 110 rods are spaced and insulated from the casing by washers 56. It will be obvious that such an arrangement provides a mechanical connection of the brush rods to the casing, or other support, the rods being separately 115 insulated from the supporting means. Either one of the oppositely disposed rods of each pair may be made the armature terminals.

It will be apparent that the relative po- 12o sitions of the ln'ush-holders, pig-tail connections and cross-coni'iectors, on the brush rods, may readily be changed without departing from the general scope of this in vention. 1

It should be understood that it is not desired to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

It is claimed and desired to secure by Letters Patent:

1. In a dynamo-electric machine, a casing provided with spaced openings, rods passin through said openings into said casing and insulated ther from, means for mechanically connecting said rods to said casing and holding the same in position, and a plurality of conducting elements mounted on said rods within said casing, said rods passing through alined openings in said elements, each rod being mechanically connected to all of said conducting elements and being electrically connected to one only 01 said elements.

2. In a dynamo-electric machine, a casing provided with spaced openings, rods passing through said openings and insulated from said casing, means for mechanically connecting said rods in position, brush-holders mounted on said rods, brushes in said brush-holders and electrically connected to said rods, and means for electrically connecting alternate rods, said means comprising a plurality of spaced and insulated conducting elements provided with alined openings through which said rods pass.

3. In combination, a brush-holder, a brush movable relatively to a portion thereof and guided thereby, and means secured in operative relation to said holder for resiliently urging said brush to operative position, said means comprising a helical spring fixed at one end and extending with its axis at an angle to the direction of movement of said brush, the other end of said spring being movable in a direction at right angles to the axis of said spring when in normal and unbiased condition and bearing upon the brush, the spring being flexed from normal position when said spring and brush are in normal operative relationf i. In combination, a brush-holder, a brush mounted thereon, and a helical spring fol lower fixed at one end and having its other end movable in the general. direction of movement of the brush and adapted to exert pressure on said brush, the pressure exerted by said spring being due to fiexure thereof.

5. In combination, a brush-holder, a brush movable thereon, a helical spring bearing at one end on said brush, and an abutment on which the other end of said spring is fixedly mounted, the axis of said spring being at an angle to the direction of movement of said brush and the end of said spring bearing on the brush being movable in the same general direction as said brush, and said abutment being adjustable to vary the degree of fiexure of said spring when the end thereof bears on said brush.

6. In combination, a rod, a brush-holder comprising spaced arms mounted on and movable about said rod, and a bru,li-carrying portion. supported by said spaced arms, an abutment member mounted on said rod between said spaced arms and angularly adjustable about said rod, means for clamping said spaced arms and said abutment member in operative position on said rod, and a helical spring having one end secured to said abutment and extending toward said brush-carrying portion, the other end of said spring being in position to bear upon a brush carried by said brush-holder and to exert a pressure on said brush in a direction at an angle to the axis of the spring.

7. In combination, a brush-holder, a brush movable thereon, a member held in position on said brush-holder and having an opening therethrough, and a helical spring mounted on said member with its axis at an angle to the direction of movement of said brush and held in position thereon by engagement of one end portion thereof with threads of a screw passing through said opening, the other end of said spring bearing on said brush and being movable in the same general direction as said brush on flexure of said spring.

8. In combination, a brush-holder comprising a plurality of spaced arms and a brush-receiving portion carried thereby, a member mounted between and adjustably held in position through the frictional engagement thereof by said arms, a helical spring secured at one end to said member, and an insulating member fixed to the other end of said spring and bearing on said brush.

9. In combination, a brush-holder, a brush movably aounted thereon, means for resiliently urging said brush to operative posiion, said means comprising a helical spring fixed at one end, the other end thereof being movable, and the free end of the wire forming said spring being tapered, and a washer secured to said free end of the spring by means of a screw passing through said washer and in threaded engagement with the tapered end portion of the spring, said washer bearing at its edge on said brush.

10. In combination, a brush-holder, a rod on which said brush-holder is mounted, a member forming an abutment and adjustably mounted ior angular movement about said rod, said abutment member being open at one side whereby it is capable of being disposed in operative position on said rod by movement thereof transverse to the axis of said rod and in the direction of a radius of said rod, and a spring having one end supported by said abutment.

11. In a dynamo electric machine, a casing, electrically conductive rods each of which has an end portion passing through said casing and secured in operative position therein and insulated from each other, a brush-holder mounted on each of said rods adjacent the other end of the same, and means for electrically connecting alternate rods said means comprising a plurality of In testimony whereof, the signature of the spaced and insulated conduct-111g elements inventor 1s aflixed hereto 1n the presence of having alined openings through Which certwo Witnesses.

tain of said rods pass, said conducting ele- LOUIS C. NICHOLS. ments being mounted on and secured in op- Vitnesses:

erative position relative to an intermediate L. A. PHILLIPS,

portion of said rods. G. E. REIFF.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

